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Depth of water sensing 1

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alternety

Computer
May 31, 2003
89
I would like to monitor the water depth in well. Maximum depth is 500" and minimum is 0'.

I have been thinking pressure sensor but everything I have found is quite expensive packaged sensors.

Any ideas on other ways to monitor depth or sources of something I can use for a sensor in a 500' well.
 
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itsmoked - I have some of the multi-winding ones but this is not one of them. The range of possible flow is pretty large and with potentially small increments. That is why I chose the variable speed. It is something to think about if this noise thing turns out to be related to the variable speed. A PLC with more relay outputs maybe. I really wonder if it is simply a defective pump.

The contractor has bled the motor twice. He says he is sure there is no air. We purged the system while filling and had the system running for 3 days to purge all the air out with the air extractors.

The pump should not be doing anything funny. The calculations have the pump matched pretty closely with the full flow of the system. He pays attention to things like flow rate in pipes and things like that. There are a lot of little details if you do all the sizing things that are really necessary. The software does all the hard work so human error is reduced to an almost NASA like level (well NASA management anyway). I played with valves a bit and I really don't notice a significant change in pump noise as I close off loops. The contractor tried fiddling with the pressure sensor range and got to a point where there was severe hunting and the motor made some really nasty noises - probably near 0 volts. My PLC may not want to turn things off by going to 0 volts. I called Omega and the tech support guy recommended the CNi 16D52. I am looking at it. The 53 is probably more useful in that it has one analog out and one relay. I am not sure yet why the D. I have to read more documentation. It may be needed to have a setpoint using their panel input. It sure looks simpler than writing a program.

I am not sure exactly what your guy means about a relief valve. He may be thinking about the bypass valve commonly used to accomplish what I am going for with the pressure thing. Typicaly these systems run the circulator at full sppeed all the time and have a bypass valve on the manifolds to return excess water when there is less than full heat demand in the loops. This, in effect, controls the pressure across the system like I am trying to do. But it seemed ugly and not particularly energy efficient. By feeling pipes and things you can pretty much identify the motor as the source.
 
No chance of debris in the pump? How much effort is it to strip and check the impeller? The little Grundfos pump in my CH system is pretty quiet and it is fairly easy to strip down. Don't damage the sealing faces! Mine's a three-speed type, so not as sophisticated as yours.


----------------------------------

One day my ship will come in.
But with my luck, I'll be at the airport!
 
I am not familiar with the particular pump, and grasping at straws here, but does it have to be orientated a certain way ? Motor up, motor down, motor horizontal, etc...
 
The pumps do have to be in a particular orientation (horizontal I think) and they are.

There should not be anything in the system. Nothing was soldered. All the copper is crimped. I will ask the contractor about it though. I have asked him to send me an electronic picture of the system so I can post it here.
 
Check the pump orientation is actually correct ! The small hot water circulating pumps I have used in solar hot water systems definitely require a vertical motor orientation.

The pumps I have seen, typically use a magnetically coupled rotor and a single ceramic wet bearing. The rotor is supported by the attraction of the rotating magnetic field as well as the bearing. If the shaft is horizontal, the rotor can "fall" slightly crooked when the pump is turned off. When powered up again. the rotor can then sometimes wobble or become unstable somehow, (not always) and create a fluttering noise.


 
We are getting a replacement pump in to see if that fixes it. We will also take apart the current one and see if there is something in the pump. It is starting to get chilly and there is no antifreze in yet.

itsmoked - have you decided what you are going to do for your heating system?

I am having a real problem comming up with an affordable PLC solution to my control problem.
 
Affordable PLC? Check out the TWIDO.


Look on the right side for the starter packs.

These are very powerful and cheap. I think they are even wireless programmable. Very small footprint.


My furnace?

I went all over the place on this choice. Man! I did extensive research on the hydronic wall jobs. But didn't want the headache of insulating more than a dozen lines staring from a manifold.

So then I looked into an air handler with a water heated coil. This had a ton of great advantages. But after crawling around under the house for a day estimating piping for it, it became clear I would need to do over 140 solder connections while laying on my back in limited space in the dark. I nixed that too <sniff>.

I ordered a multistage gas furnace with a variable speed blower with 93% efficiency.

Spent the last two days routing gas and electricity to where it will reside in the attic.
 
Thanks, I will look at them. I actually have their site up on another screen at the moment.

PEX would allow a continuous run without joints. And it is flexible. You need a tool but you could probably get a plumber or heating person to make the joints.

Appears too late for this, but just FYI. If you need to rearrange water pipes or anything keep this stuff in mind.

 
Great thread, classic. Alternety, another way u can control ur flow rate is by running the motor output through an infinitely variable transmission. That way the motor only cares about on/off and runs at constant speed. Controlling the IVT lets u vary the pump rpms and thus flow rate.

chris
 
We're not quite at 200 posts yet... ...anyone know any good jokes?

PS: It's been near freezing +0.7C (33F) the past few nights (NS, Canada). If this keeps up, I might eventually have to turn on my simple cheap electric heaters.

 
VE1BLL you are so cruel... [cry]

I pay 26 cents US a kWhr...

1500W heater X 8hrs = 12kWhr

12kWhr X 0.26 = $3.12

$3.12 X 30Days = $93.60/Month

and that's just one room.[cry][cry][cry][cry][cry]

People wonder why we pay $300 for a cord of Oak.[laughtears]
 
26 'Mericun cents per kWh... geesh. Here in NS, Canada it is around ten Canadian centettes per kWh. With taxes it might round up to something close to US$.10 per kWh. In central Canada (Hydro, nookes) it is as low as around Cdn$0.05 per kWh.

My total heating bill has always been just under Cdn$1k per year (based on integrating under the winter hump). With the latest rate hikes, it might go just over Cdn$1. We keep the house warm at 21C and 18C at night. 2800 sg ft plus basement.

The key is to invest the capital into passive solar (22 sq m of glass facing South, fully shaded in summer by the way) and very good insulation (walls R30, roof R40, outside basement R10). These features tend to be reliable, don't need electrical power to run, and are very, very, very quiet.

I've seen my share of heat pump systems where the electrical power consumption for all the pumps and controllers was higher than my baseboard heaters.

It's nice to have hobbies, but not a heating system...

How's the post count now, 175?

 
Why not just move to a land of palm trees blue skies and balmy tropical breezes ?
 
V1BLL

Please send:
EXTENSION CORD, LONG, 8AWG, PLUGGED IN

Warp... That usually comes with too hot, hot, hot[flame] that, last I looked, costs even more to remedy than cold cold cold.
 
No no no, that's not nearly engineerish enough. Even cave men had extension cords. V1BLL please build a large tesla coil designed to direct flux primarily into the southern Ohio region. I will correspondingly build several receiving coils to receive said 5 cent power.
 
NO! NO! Don't listen to him!! Point it at Northern Calif!!
 
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